The Role of Unprotected Areas in Enhancing Ecological Network Resilience

ABSTRACT Conservation has long prioritized lands inside protected boundaries, while external areas are overlooked. Yet species flow across human‐drawn lines, and the functions of off‐protected zones merit renewed attention. Using the Ecological Conservation Redline (ECR) in Zhejiang Province as a case, we compared the roles of ecological patches inside the redline (EPIR) and ecological patches outside the redline (EPOR) from an ecological network resilience perspective. To this end, node load was used to represent patch‐level ecological burden, and different pressure regimes were generated by tuning the load‐allocation parameter: a light‐load regime reflects lower overall pressure with relatively dispersed loads, whereas a heavy‐load regime indicates elevated pressure concentrated on key nodes. Building on this setup, we simulated disturbance propagation using a cascading failure model to quantify how patches inside and outside the redline contribute to network resilience. Results indicate that EPIR and EPOR play complementary “core” and “bridging” roles, respectively, in sustaining cross‐regional resilience; even under full protection of EPIR, degradation of EPOR can still precipitate network‐wide collapse. Patch criticality was also strongly contingent on load level: under light loads, early failure of low‐connectivity patches can rapidly erode overall resilience; under heavy loads, system stability depends largely on “extremely important” patches, all of which lie outside the redline. Based on these findings, EPOR were classified into Ecological Reserve Areas, Ecological Buffer Areas, and Ecological Transit Corridor Areas according to their spatial relationship with the ECR and functional attributes. We further assigned three management intensities based on their marginal contributions to resilience, forming a differentiated “three‐category–three‐level” management framework. Overall, our findings suggest that unprotected areas contribute to ecosystem stability and connectivity no less than patches within protected areas and may exhibit even greater structural and functional value under specific disturbance scenarios, thereby informing regional ecological pattern optimization and conservation policy refinement.